Integral sole face club head

ABSTRACT

A golf-club head has a first half of shaped crown integrally including skirt and a hosel connection having a hosel attachment opening. A second half is a bottom plate having an integral striking face with built-in angle of loft so that the two halves are welded together providing solder leakage concentrating on the lower part of the head. A hosel is welded to the crown at the hosel connection.

FIELD OF THE INVENTION

This invention relates to a method of manufacturing sports equipment,specifically a golf club made of two head halves and a hosel.

DISCUSSION OF RELATED ART

The traditional forged component structure of a golf-club head has fourpieces, a crown, a hosel, a faceplate, and a sole in clockwise directionof FIG. 5. The crown of the traditional four-piece golf club is weldedto the sole at its upwardly extending skirt so that leakage of solderwire is about 8-10 g, which concentrates on the upper part of the head,raising the head's center of gravity. This makes the total solderwelding weight of about 22 g which can affect the golf club head weightdistribution and center of gravity or CG in short. Therefore, loss ofprecision and other center of weight problems have long been unsolved infour-piece type of golf-club head. Since the weight distribution of aclub head is generally uniform, in order to correct the center ofgravity one must add inserts commonly made of heavier material to thesole and skirt of the head.

Traditionally, the sole and skirt are integrally formed from one sheetof metal as seen in FIG. 5 although it is preferred to have a thickersole than the skirt. Unfortunately, the traditional method makes thisdifficult because the sole and skirt are formed from a uniform thicknessplanar metal sheet. Additionally, the welding junction of the fourpieces that defines the hosel connection requires excessive solderaccumulation causing a variety of weight distribution and toleranceproblems.

Further, there are issues with regard to welding the sole, crown andface to one another (each other). Each positioning of the pieces inproduction cannot guarantee the same profile of the resulting faceangle, i.e. the angle of loft for every product.

SUMMARY OF THE INVENTION

The club head of this invention has the faceplate with sole made in asingle piece like the crown with the integral skirt. The club head alsoincludes a stretched hosel connection. A workpiece pattern is preparedand a mold draws the faceplate and sole, which is erected from thefaceplate along a transverse line at a built-in angle of loft. Thus, thefaceplate is formed from a flat sheet of metal into a face-sole unit.Similarly, another mold draws the crown of the golf-club head tointegrally include a skirt and stretched hosel connection. Thus, thecrown is formed from a second flat sheet of metal into a crown-skirtunit. In certain crown shapes, the male mold member may have to be madecollapsible.

Optionally, the hosel may be integral to the faceplate formed of asingle piece of metal and welded to the crown at the hosel connectionwhen the club parts are welded along an interface formed between theface-sole unit and crown-skirt unit. Also, the hosel and face of theface-sole unit can be made of two separate pieces of metal and joinedtogether. The hosel and face can be joined together before or after thewelding of other parts.

The hosel connection has a hosel attachment opening receiving a standardcylindrical hosel with precise tolerance. The crown-skirt unit is thenwelded to the face-sole unit along a seam line and to the hosel in orderto form the golf-club head. In traditional structures, the sole isintegrated with skirt and is then welded with the crown, striking faceand hosel. The striking face commonly has grooves, which indicate thesweet spot.

Welding the crown-skirt unit to the face-sole unit advantageously lowersthe center of gravity of the head compared to the traditional componentwelded structure. In the present invention, the welding position islowered to the lower side of the head and the bottom at the face-soleunit with an in-leakage of solder of about 3 g, which concentrates onthe lower part of the head. Thus, a portion of weight is shifted fromthe upper part of the head, where the crown and the skirt wouldotherwise have been welded, to the lower part of the head. Incomparison, conventional golf club head includes three components of acrown, a sole with a skirt, a faceplate welded via the respective seamlines. The club head also has a hosel, which protrudes into the cavityof the club head through an opening defined by converging edges of thethree components and welded thereto.

According to the present invention, the junction between the faceplateand the sole is completely spared any welding seam that may cause theunevenness of the sole bottom and the irregular loft angle plagueassociated with conventional golf club heads. Overall, the net effect isto guarantee the production of club head with same external shape or theangle of loft that was difficult to achieve in the past because theseparate face had to be positioned and welded to the sole as well as thecrown. It means the head's center of gravity CG can be lowered by about1-1.5 mm or more compared to that of a head made in a traditionalfashion. A 1 mm CG shift should substantially affect the sweet spot. Inaddition, the integral structure of the face-sole unit ensures thedurable junction of the face and sole with eliminated possibility ofcracking even after repeated high impacts during the life of the clubhead.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded perspective view of the club head according to thepresent invention depicting the steps to make the same.

FIG. 2 is a perspective view of the club head according to the presentinvention.

FIG. 3 is a side sectional view of the club head of FIG. 1.

FIG. 4 is a side sectional view of the prior art club head.

FIG. 5 is an exploded view of the prior art club head.

FIG. 6 is a perspective view of the prior art club head of FIG. 5.

FIG. 7 is an exploded view of the club head according to the presentinvention.

FIG. 8 is a perspective view similar to FIG. 2 for comparison with theprior art club head.

FIG. 9 is a perspective view of the crown according to the presentinvention.

FIG. 10 is a perspective view of the prior art crown.

OBJECTS OF THE INVENTION

1. Relocating welding seams to the bottom, and avoiding skirt to crownwelding as well as face to sole welding. Lowering the sweet spot by1-1.5 mm.

2. Guarantying the club head production with same external shape or theangle of loft.

3. Increasing strength at the junction of the face and sole witheliminated possibility of cracking even after repeated high impacts.

4. Making a design where welding solder does not change the center ofgravity as much. Save 8 grams of welding weight and have only about 14grams of welding concentrated in the lower sole plate.

5. Using the welding solder weight savings to lower the center ofgravity by having a thicker sole plate.

6. Creating a better hosel connection by having a one-piece stretchformed hosel connection to allow tighter tolerance.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

A mold may use a wide variety of metal forming methods such as forging,casting, stamping, rolling, or super plastic deformation to make theparts to the golf-club head. One method in current use is discussed inSong, U.S. patent Ser. No. 10/672,463, which is incorporated herein byreference. Here a wide variety of means for forming parts can be used.Although a wide variety of means for forming parts can be used, it ispreferred to make the face-sole unit from super plastic deformationtechnique. The super plastic deformation technique is not required forany part of the invention. Also, titanium is not required, but preferredas the best mode.

Referring to FIGS. 1 and 2, the key to the club head 100 of thisinvention is the faceplate 120 a with sole 120 b offered in single piecelike the crown 110 a with skirt 110 b. The club head 100 also includes astretched hosel connection. A workpiece pattern 105 is prepared and amold draws the faceplate 120 a and sole 120 b erected from the faceplate120 a along a transverse line 116 at a predetermined angle, whichdefines the angle of loft for the subsequent club head 100 in FIG. 2.Therefore, the faceplate 120 a is formed from a flat sheet of metal intoa face-sole unit 120. Similarly, another mold draws the crown 110 a ofthe golf-club head to integrally include a skirt 110 b and stretchedhosel connection 117. Thus, the crown 110 a is formed from a flat sheetof metal into a crown-skirt unit 110. In certain crown shapes, the malemold member may have to be made collapsible. According to the prior artit is well known how to make a male mold member collapsible for removalfrom the workpiece.

As can be seen in the prior art clubs, the hosel 140 may be integral tothe faceplate 120 a formed of a single piece of metal and welded to thecrown at the hosel connection when the club parts are welded along aninterface formed between the face-sole unit and crown-skirt unit. Thepresent invention does not require a hosel 140 and face 120 a to be madeof one piece of metal and thus integrally formed. The hosel 140 and face120 a of the face-sole unit 120 can be made of two separate pieces ofmetal and joined together. The hosel 140 and face 120 a can be joinedtogether before or after the welding of other parts.

The hosel connection has a hosel attachment opening 115 receiving astandard cylindrical hosel 140 with precise tolerance. The crown-skirtunit 110 is then welded to the face-sole unit 120 along a seam line 112and to the hosel 140 in order to form the golf-club head 100. Intraditional structures, the sole (bottom) is integrated with skirt andis then welded with the crown, striking face and hosel. The strikingface 120 a commonly has grooves not shown, which indicate the sweetspot.

FIG. 3 shows a sectional view of the club head 100 that has been sawn inhalf after assembly. The wider outside portion of the hosel 140 matchesthe circumference of the shaft not shown, and the narrower insideportion 142 of the hosel 140 fits inside the crown-skirt unit 110. Thehosel 140 is connected to the crown-skirt unit 110 at the hoselconnection opening 115. A weld 112 attaches the face-soul unit 120. Onthe right side is depicted the other half of the club such that the twohalves of the striking faces are facing each other.

Welding the crown-skirt unit 110 to the face-sole unit 120 should lowerthe center of gravity of the head compared to the traditional componentwelded structure. In the present invention, the welding position 112 islowered to the lower side of the head and the bottom at the face-soleunit 120 with an in-leakage of solder of about 3 g, which concentrateson the lower part of the head. Thus, a portion of weight is shifted fromthe upper part of the head, where the crown and the skirt wouldotherwise have been welded as seen in FIG. 4, to the lower part of thehead as seen in FIG. 3. FIG. 4 shows conventional golf club head 200having three components of a crown 210, a sole 220 with a skirt, a faceplate 230 welded via seam lines 212 a, 212 b and 212 c. The club head200 also has a hosel 240, which protrudes into the cavity of the clubhead through an opening defined by converging edges of the threecomponents and welded thereto.

In contrast, it is clear from FIG. 3 that the junction between thefaceplate 120 a and the sole 120 b is completely spared any welding seamthat may cause the unevenness of the sole bottom and the irregular loftangle plague associated with conventional golf club heads.

Overall, the net effect is to guaranty the production of club head withsame external shape or the angle of loft which was difficult to achievein the past because the separate face had to be positioned and welded tothe sole as well as the crown. It means the head's center of gravity CGcan be lowered by about 1-1.5 mm or more compared to that of a head madein a traditional fashion. A 1 mm CG shift should substantially affectthe sweet spot.

In addition, the integral structure of the face-sole unit 120 ensuresthe durable junction of the face and sole with eliminated possibility ofcracking even after repeated high impacts during the life of the clubhead.

FIG. 5 shows an exploded view of the prior art. The crown 210, thestriking face 230, the sole 220, and the hosel 240 are connected to eachother manually and welded along their interfaces forming a hollow golfclub. As seen in FIG. 5, the placement of the various elements requiresmanual skill. FIG. 6 shows welding of the assembled prior art club shownin FIG. 5. The hosel 240 is welded at hosel welding 218, which is builtup and manually configured. To make such club requires three seam lines212 a, 212 b and 212 c.

FIG. 7 shows the exploded view of the present invention. The hosel 140rests in a pre-configured position in the crown-skirt unit 110. Theface-soul unit 120 is connected. The sole welding to the crown skirt 110is toward the bottom of the club, lowering the center of gravity afterwelding as opposed to raising center of gravity common in the prior art.

FIG. 8 shows the assembled present invention having a micro weld 118between the hosel 140 that is a much smaller weld required. With asmaller weld the tolerance is tighter and the center of gravity changeis smaller. Between the face-soul unit 120 and crown-skirt unit 110 thesingle seam line 112 is present.

When the crown 110 a and skirt 110 b are integrally formed, thecrown-skirt unit 110 is locally stretched to form a hosel connectionopening 115 and throat portion 117, which together constitute anintegral seat (arch) 920 shown in FIG. 9.

The hosel 140 is commonly cylindrical having a pair of terminating ends.A first end inserts into the crown 110 a on the club head and a secondend attaches to the shaft not shown. The hosel 140 is placed in thehosel receiving opening 115. The hosel member portion 142 fitting intothe crown 110 a is of smaller cross-section than the portion of thehosel member 140 that does not fit into the inside of the crown 110 a.The hosel 140 is then welded to the hosel (connection) area around theopening 115. After the connection welding, the shapes of throat part orhosel attachment area 117 on all heads are standardized having muchsmaller variances than before. The hosel rests on the hosel connectionopening 115 so that a welder can more easily position the hosel.

The top portion of the hosel is larger than the hosel opening 115 on thecrown 110 a. The top portion of the hosel allows the hosel to rest inthe opening without having to position the hosel (moving) into or out ofthe opening. The bottom cylindrical portion of the hosel designed toconnect to the crown is sized to fit into the circular opening. Thebottom cylindrical portion does not need to be snugly fitted, and canhave some slack. The hosel attachment area 920 can be formed as a roundprotrusion drawn from and protruding from the top of the crown. Theround protrusion 920 would then have a terminating circumference. Thehosel attachment area should have a terminating circumference matchingthe circumference of an annular protrusion defined by the diametrictransition between the top and inserted portions of the hosel 140.During assembly, the top portion of the hosel matches with thecircumference of the hosel attachment area so that after welding andsurface finish, the weld between the hosel attachment area and hosel isa smooth transition and not noticeable. The top portion of the hoselforms the outside circumference of the hosel.

FIG. 10 shows the crown of the prior art having no enclosed opening tosecure the hosel 240 prior to and during welding. The crown 110 of theprior art has an open connection 940 that does not provide tighttolerance.

The thickness of the sole 120 b can be greater than that of the skirtplate thickness. The side and bottom parts of a traditional four piecehead are of basically uniform thickness with a welding weight of around22 g. But as the welding weight of the present invention is about 8-10 glighter than usual, the thickness of the sole can be increased forgreater moment of inertia and change in center of gravity.

By utilizing different thickness of metal for the face-sole unit 120shifting the designed center of gravity or change of moment of inertiais possible according to the present invention.

Additionally, using titanium for the head with the method of superplastic deformation (SPD) or severe plastic deformation forming thefaceplate 120 a may have more varieties of thickness to change theweight distribution of the club head, so as to lower the center ofgravity of the club.

The SPD formation allows the face-sole unit 120 to have its middleportion 121 thicker than the rest though other variations in thicknessalong the entire walls of the face-soul unit 120 can be realized. Theadjustment of sectional thickness and structure of the striking faceenhances the bouncing rate and the striking distance of the club. Thecrown-skirt unit 110 and the face-sole unit 120 of the present inventionmay be welded by SPD formation.

After welding, the club head is surface finished and then can beattached to a shaft to form the golf club. The surface finish can beprepared so that the entire connection appears as a single continuousshaft protruding from the crown.

CALL OUT LIST OF ELEMENTS

-   100 Golf-Club Head-   105 Workpiece-   110 Crown-Skirt Unit-   110 a Crown-   110 b Skirt-   112 Seam Line-   115 Hosel Attachment Opening-   117 Hosel Connection with Arch-   118 Micro Weld-   120 Face-Sole Unit-   120 a Faceplate-   120 b Sole-   121 Thicker Face Portion-   140 Hosel-   142 Hosel Member Portion Fitting Into Club-   200 Prior Art Club Head-   210 Crown-   212 a, 212 b, 212 c Seam Lines-   218 Hosel Welding-   220 Sole-   230 Face Plate-   240 Hosel-   920 Hosel Seat-   940 Open Hosel Connection

1. A golf-club head comprising: a. a crown integrally including skirtand a hosel connection having a hosel attachment opening; b. a bottomsole having an integral striking face extending from said bottom sole,said bottom sole and striking face being welded to said crown and skirtalong a closed loop of seam line, wherein solder leakage concentrates onthe lower part of said head; and c. a hosel having a lower section forinserting into said hosel attachment opening and an enlarged sectionwith an annular transition, which is formed between said lower sectionand seated on said hosel connection for welding attachment thereto. 2.The golf-club head of claim 1 wherein said hosel attachment opening isround and receives a standard cylindrical hosel.
 3. The golf-club headof claim 1 wherein said crown and skirt are integrally formed to includean arch at said hosel connection.
 4. The golf-club head of claim 1wherein the thickness of said bottom sole is greater than the skirtplate thickness.
 5. The golf-club head of claim 1 wherein said crown andskirt are integrally formed to include an arch at said hosel connection,which terminates in a circumference matching the outside circumferenceof said annular transition of said hosel.
 6. A golf-club headcomprising: a. a crown formed from a single sheet of metal to integrallyinclude a skirt and a stretched hosel connection having a hoselattachment area (opening); b. a bottom sole having an integral strikingface extending from said bottom sole, wherein solder leakageconcentrates on the lower part of said head; and c. a hosel formedintegral to said striking face and sole unit for receiving a shaft, saidhosel having a lower section and an enlarged section with an annulartransition, which is formed between said lower section and seated onsaid hosel connection for welding attachment thereto, whereby said crownand skirt unit is welded to said bottom sole and striking face unitalong an interface formed therebetween.
 7. The golf-club head of claim 6wherein said hosel attachment opening is round and receives a standardcylindrical hosel.
 8. The golf-club head of claim 6 wherein said crownand skirt unit is integrally formed to include an arch at said hoselconnection.
 9. The golf-club head of claim 6 wherein the thickness ofsaid bottom sole is greater than said skirt plate thickness.
 10. Thegolf-club head of claim 6 wherein said crown and skirt unit includes anarch at said hosel connection, which terminates in a circumferencematching the outside circumference of said annular transition of saidhosel.
 11. A golf-club head comprising: a. a crown formed from a flatsheet of metal so that it integrally includes a skirt and a hoselconnection; b. a bottom sole having an integral striking face extendingfrom said bottom sole and being welded to said crown, wherein solderleakage concentrates on the lower part of the head; and c. a hoselwelded to said crown at said hosel connection.
 12. The golf-club head ofclaim 11 wherein the hosel attachment opening is round and receives astandard cylindrical hosel.
 13. The golf-club head of claim 11 whereinthe crown and skirt are integrally formed to include an arch at thehosel connection.
 14. The golf-club head of claim 11 wherein thethickness of the bottom sole is greater than the skirt plate thickness.15. The golf-club head of claim 11 wherein said crown and skirt areintegrally formed to include an arch at said hosel connection, whichterminates in a circumference matching the outside circumference of saidannular transition of said hosel.